Depending on your social circle, the event invites are the problem that dragged me back. I don’t care much about the photos and updates, but:
“Hey! I’m throwing a party”... “Oh shit, I need to go out of my way to make sure so-and-so gets an invite”.
Eventually, one of my friends told me “You not being on FB is adding work for the rest of us. Someone always needs to go out of their way to mention everything to you”.
I use snapchat (and somewhat instagram). That does the trick.
Heck, I'm mostly over social media.
I dont care about the daily activities of my friends, they arent that interesting. Food, work, food, work, food, gym, bar, selfies.
I can google image that crap.